1. Field of the Invention
The present invention relates generally to a lockset, and more particularly to an innovative one which is designed with a safe linkage structure allowing for unlocking by pressing.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
Locksets of various types and models are widely used on various occasions. A lockset is generally arranged on left and right doors, permitting to unlock both doors in the event of emergency, or unlock a single door at ordinary times. Generally, a lockset is separately set onto a door's upper and lower ends to fix the door. However, the users have to climb up via a ladder to the upper end of the door for releasing the bolt, and then go down to the lower end of the door for unlocking. So, there occur some problems such as: security hazards of falling down, relatively slow unlocking speed and untimely escape in emergency situations. Hence, an outdoor linkage lockset has been developed to address aforementioned problems. Wherein, a push handle is set on the middle of the door. A locking structure located on upper and lower ends could be driven by pushing horizontally the push handle. However, this kind of linkage lockset lacks of locking functions, so it could only be applied to an exit door rather than the doors of warehouses, factories or households, etc. Moreover, this outdoor mounting design is also unsuitable for above-specified patterns, so there are still some disadvantages with lower applicability. Hence, such outdoor linkage lockset has gradually been replaced by a handle pressing linkage lockset, which is researched and improved in the present invention for its linkage structure.
A conventional lockset with handle pressing linkage structure comprises a linkage structure connected to the door handle, an upper and a lower sliding seat driven by the linkage structure and a bolt bar located on the end of each sliding seat. When the door handle is pressed by the user, the upper and lower sliding seats could be driven by the linkage structure far away into a protruding state, so the bolt bar is separately fixed on the doorframe and ground for locking purpose. On the contrary, when user pulls up the door handle, the upper and lower sliding seats are mated to each other for unlocking purpose.
However, in the event of fire alarms or other emergency situations, most people are eager for unlocking from the exit door by directly pressing the door handle (a habit for using a press handle). Yet, at this moment, the action of pressing the door handle will lock the door, causing the loss of optimum opportunity for escape and subsequent security hazards. Therefore, the design of the conventional lockset cannot meet the common users' needs since it is contrary to their operating habit.
Moreover, as mentioned above, one of the exit doors is generally locked under normal circumstances. However, referring to the left diagram in FIG. 1, when the conventional lockset is in a locked state, the door handle A is in a pressing state. So, this will not only cause misunderstanding that the door can be directly opened by pushing, but also the handle in a normal pressing state looks inconsistent, making both doors aesthetically unpleasing.
Besides, referring to FIG. 1, even though two doors are in an unlocked state, people will have an illusion to open the door by pressing door handle A, since the door handle A is in a flat state. This will significantly reduce the ease of operation and utilization. So sum up, the conventional linkage structure of a lockset is still difficult to meet the users' operating habit, resulting in potential security risk and inconvenience in operation.
Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy.
Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products.